Cold start of metal melting furnace

The cold start process requires sufficient time for the lining material to expand reversibly and seal the cracks caused by thermal shock before any molten metal contacts the lining.

During the cold start process, 3 to 4 K-type thermocouples should be used to detect the temperature. The thermocouples should be placed close to the furnace wall or bottom. For the metal melting furnace, the temperature of the thermocouple in the middle of the effective coil is the control temperature. In addition, gas combustion can be added at the bottom of the furnace to help reduce the temperature difference between the upper part of the furnace and the entire furnace lining. …

For example, the cold start time of a 5-ton furnace: within 2h, the solid material in the furnace is heated to 1100°C (heating rate: 4t～15t furnace does not exceed 150°C/h, and larger than 15t furnace does not exceed 100°C/h). Keep the temperature at 1100°C for 3h, and quickly melt the charge after the heat preservation is over, and put it into normal use. …

Start with low power transmission, gradually increase the power (to 20% to 30% of the full power for 15 minutes), make the small cracks appearing when the furnace lining is cooled, and finally send the full power).